In the state-of-the-art there are several devices developed for patients whose locomotion function is either lost or declined due to spinal disorders, orthopaedic surgeries and central nervous system disorders to redevelop and improve their walking ability.
The basic operation of these devices which are generally called walkers or walking aids is designed to relieve the patient of a significant part of body weight by means of various sling mechanisms and thereby allow the patient to receive rehabilitation treatment by performing only walking and foot movement exercises for extended periods.
However, in these devices, parts that provide the basic advantage for the patient to regain locomotion function are not the sling mechanisms which reduce body weight but stepping mechanisms which allow foot and walking movements.
The closer the movement model achieved by the stepping mechanism is closer to the natural walking motion, the easier the brain refocuses on the learnt walking movement and the motor nervous system repeats the same movements. For this reason, the main motive behind the development of these devices is to achieve a movement model that is closest to the natural walking movement.
Some of the prior art devices are based on treadmills, wherein the patient's weight is carried by extra equipment and leg and foot movements are coordinated externally for proper walking exercises. The invention disclosed in the U.S. Pat. No. 6,821,233B1 numbered U.S. Patent is an example of this type of devices. The most important technical problem related to the devices that depend on a treadmill is that the device does not provide any assistance in adapting patient's stepping movements to the natural movement.
The invention disclosed in the US2005239613A1 numbered U.S. Patent Application may be provided as an example for mechanisms which are currently used in numerous walkers and intended for supporting patients by carrying their weight. The said application discloses how the patient's weight is supported, while no information is present regarding walking therapy.
Another prior art device belongs to Jungwon Yoon (YOON JEONG WON) and is disclosed in “Machine and Its Applications to Locomotion Interface and Lower Limb Rehabilitation, Gwangju Institute of Science and Technology, 2005, 124p, Advisor: Prof. Jeha Ryu” and the KR20040072197A numbered Korean Patent Application.
In the invention according to the said patent application, walking movement is simulated by vertical lifting elements that support forefoot and hindfoot's vertical movement. In order to fully simulate walking movement, one of the vertical lifting elements which provide mechanism's front and rear vertical movement should have joint freedom. An angle α is present between Position 1 and Position 2 as seen in FIG. 21. Since this angle vary depending on the patient's weight and forces it exerts, the elliptical orbit formed by forefoot and hindfoot during walking movement cannot be fully simulated.
In the invention according to the present application formation of an angle α such as in the Jungwon Yoon invention is avoided and the motion curve formed by the foot during walking is simulated in such a manner that it is controlled and close to actual walking movement.